Insurer IAG will complete its rebuild or repair programme by December 2015, the company told about 120 customers at the first of three meetings for policyholders in Christchurch last night.

About 500 new homes and 450 major repairs (those with more than $100,000 damage) would be completed by June next year, in addition to the 100 new homes and 50 major repairs it will have completed before Christmas this year.

About 900 customers had been helped to buy existing homes.

IAG said it would confirm the status of overcap claims, in other words whether a property is economic to repair, or needs to be rebuilt, by December 20.

IAG chief executive Jacki Johnson said she understood customers' frustrations and the company intended to provide "some clarity" before Christmas.

Worst-affected customers including the very elderly, those with young family members or those whose homes were uninhabitable would take priority.

Johnson and other senior IAG staff faced a continuous stream of questions from customers last night, ranging from whether those time frames would be met to questions about drilling, property maintenance and silt removal.

IAG Canterbury earthquake recovery executive manager Dean MacGregor said the insurer was confident it would have completed its rebuild and repair programme by the end of 2015.

However, some customers responded with scepticism.

Richard Batt, whose in-laws' Dallington home is zoned TC3 described the time frame as "a little ambitious" when the insurer was not yet able to tell homeowners when drilling would take place on their property.

IAG general manager personal lines Canterbury recovery Annette Purvis said one of the constraints was a limited number of geotech engineers.